How do I change the color of the border of a dL4 window?

The following program sets the background and foreground borders and default colors to blue and yellow, respectively.

Open #1,{"","titl,hide",40,10} As "Window" ! Hidden Window
Print #1;'255Backcolor cs ye'; ! set border and default colors
Channel 11,#1; ! make window visible

After the Channel statement, the current foreground and background colors may be changed to desired colors without affecting the border colors.